A solar generator can include a photon-enhanced thermionic emission generator with a cathode to receive solar radiation. The photon-enhanced thermionic emission generator can include an anode that in conjunction with the cathode generates a first current and waste heat from the solar radiation. A thermoelectric generator can be thermally coupled to the anode and can convert the waste heat from the anode into a second current. A circuit can connect to the photon-enhanced thermionic emission generator and to the thermoelectric generator and can combine the first and the second currents into an output current.

One or more pellicles protect a cathode, the pellicles comprised of a thin layer of material that allows electrons to pass while preventing contamination of the cathode from elements originating beyond the pellicle or contamination of an outside apparatus from elements originating on or near the cathode. The pellicle can be supported by an insulator, the insulator in turn supported by a deflecting layer. The pellicle can be maintained at a positive voltage relative to the cathode, such that a voltage gradient is created between the cathode and the pellicle that accelerates electrons emitted by the cathode away from the cathode. The pellicle is located at an appropriate distance from the cathode to allow electron transmission matching the energy of the electrons at that distance.

A photocathode can include a body fabricated of a wide bandgap semiconductor material, a metal layer, and an alkali halide photocathode emitter. The body may have a thickness of less than 100 nm and the alkali halide photocathode may have a thickness less than 10 nm. The photocathode can be illuminated with a dual wavelength scheme.

A photocathode can include a body fabricated of a wide bandgap semiconductor material, a metal layer, and an alkali halide photocathode emitter. The body may have a thickness of less than 100 nm and the alkali halide photocathode may have a thickness less than 10 nm. The photocathode can be illuminated with a dual wavelength scheme.

An electron source system utilizing photon enhanced thermionic emission to create a source of well controlled electrons for injection into a series of lenses so that the beam can be fashioned to meet the particular specification for a given use is disclosed. Because of the recent increased understanding and characterization of the bandgap in certain materials, a simplified system can now be realized to overcome the potential barrier at the surface. With this system, only low electric fields with moderate temperatures (500 C.) are required. The resulting system enables much easier focusing of the electron beam because the random component of the energy of the electrons is much lower than that of a conventional system. The system comprises an emitter of wide bandgap material, a first light source and a heating element wherein the heating element provides moderate warming to the wide bandgap material and the light source provides photonic excitation to the material, causing electrons to be emitted into an optical system to manipulate the emitted electrons.

An electron source system utilizing photon enhanced thermionic emission to create a source of well controlled electrons for injection into a series of lenses so that the beam can be fashioned to meet the particular specification for a given use is disclosed. Because of the recent increased understanding and characterization of the bandgap in certain materials, a simplified system can now be realized to overcome the potential barrier at the surface. With this system, only low electric fields with moderate temperatures (500 C.) are required. The resulting system enables much easier focusing of the electron beam because the random component of the energy of the electrons is much lower than that of a conventional system. The system comprises an emitter of wide bandgap material, a first light source and a heating element wherein the heating element provides moderate warming to the wide bandgap material and the light source provides photonic excitation to the material, causing electrons to be emitted into an optical system to manipulate the emitted electrons.

Electron source designs are disclosed. The emitter structure, which may be silicon, has a layer on it. The layer may be graphene or a photoemissive material, such as an alkali halide. An additional layer between the emitter structure and the layer or a protective layer on the layer can be included. Methods of operation and methods of manufacturing also are disclosed.

Electron source designs are disclosed. The emitter structure, which may be silicon, has a layer on it. The layer may be graphene or a photoemissive material, such as an alkali halide. An additional layer between the emitter structure and the layer or a protective layer on the layer can be included. Methods of operation and methods of manufacturing also are disclosed.

One or more pellicles protect a cathode, the pellicles comprised of a thin layer of material that allows electrons to pass while preventing contamination of the cathode from elements originating beyond the pellicle or contamination of an outside apparatus from elements originating on or near the cathode. The pellicle can be supported by an insulator, the insulator in turn supported by a deflecting layer. The pellicle can be maintained at a positive voltage relative to the cathode, such that a voltage gradient is created between the cathode and the pellicle that accelerates electrons emitted by the cathode away from the cathode. The pellicle is located at an appropriate distance from the cathode to allow electron transmission matching the energy of the electrons at that distance.

One or more pellicles protect a cathode, the pellicles comprised of a thin layer of material that allows electrons to pass while preventing contamination of the cathode from elements originating beyond the pellicle or contamination of an outside apparatus from elements originating on or near the cathode. The pellicle can be supported by an insulator, the insulator in turn supported by a deflecting layer. The pellicle can be maintained at a positive voltage relative to the cathode, such that a voltage gradient is created between the cathode and the pellicle that accelerates electrons emitted by the cathode away from the cathode. The pellicle is located at an appropriate distance from the cathode to allow electron transmission matching the energy of the electrons at that distance.